/*
 * @Author: zjf
 * @Date: 2023-08-21 15:32:20
 * @LastEditors: zjf
 * @LastEditTime: 2023-09-11 17:20:11
 * @Description: 
 */
let watermark = {}

let setWatermark = (str1, str2, str3) => {
    let id = '1.23452384164.123412415'
    str2 = str2 || getDate()

    if (document.getElementById(id) !== null) {
        document.body.removeChild(document.getElementById(id))
    }
    //创建一个画布
    let can = document.createElement('canvas')
    //设置画布的长宽
    can.width = 460
    can.height = 240

    let cans = can.getContext('2d')
    //旋转角度
    cans.rotate(-15 * Math.PI / 180)
    cans.font = '15px Vedana'
    //设置填充绘画的颜色、渐变或者模式
    //cans.fillStyle = 'rgba(200, 200, 200, 0.40)'
    cans.fillStyle = '#666666'
    //设置文本内容的当前对齐方式
    cans.textAlign = 'center'
    //设置在绘制文本时使用的当前文本基线
    cans.textBaseline = 'Middle'
    //在画布上绘制填色的文本（输出的文本，开始绘制文本的x坐标位置，开始绘制文本的Y坐标位置）
    cans.fillText(str1, can.width / 2, can.height / 2)
    if (str2) cans.fillText(str2, can.width / 2, (can.height / 2) + 22)
    if (str3) cans.fillText(str3, can.width / 2, (can.height / 2) + 44)

    let div = document.createElement('div')
    div.id = id
    div.style.pointerEvents = 'none'
    div.style.top = '0px'
    div.style.left = '0px'
    div.style.opacity = '0.15'
    div.style.position = 'fixed'
    div.style.zIndex = '100000'
    div.style.width = document.documentElement.clientWidth + 'px'
    div.style.height = document.documentElement.clientHeight + 'px'
    div.style.background = 'url(' + can.toDataURL('image/png') + ') left top repeat'
    document.body.appendChild(div)
    return id
}


//添加水印方法
watermark.set = (str1, str2, str3) => {
    let id = setWatermark(str1, str2, str3)
    if (document.getElementById(id) === null) {
        id = setWatermark(str1, str2, str3)
    }
    window.onresize = () => {
        setWatermark(str1, str2, str3)
    }
}


// 移除水印
watermark.remove = () => {
    let id = '1.23452384164.123412415'
    if (document.getElementById(id) !== null) {
        //document.body.removeChild(document.getElementById(id))
        const div = document.getElementById(id)
        div.style.display = 'none'
    }
}

const getDate = () => {
    var date = new Date();

    var year = date.getFullYear(); //年
    var month = date.getMonth() + 1; //月
    var day = date.getDate(); //日

    var now = year + "-" + month + "-" + day; // 当天
    return now
}

export default watermark